A domain-specific approach is proposed to examine the cognitive/motivational processes of children with Attention Deficit Hyperactivity Disorder (ADHD), relative to control children. These studies are unique in three ways. First, they comprise the-first comprehensive comparison of cognitive/motivational variables in ADHD vs. normal children. They examine these cognitive/ motivational variables by applying a model of achievement motivation from the developmental literature (Dweck & Leggett, 1988) to a major form of childhood psychopathology--ADHD. Second, they are the first to examine the domain specificity of motivational processes by examining multiple domains of functioning (academic, social) within a single sample of children, while holding subject variables constant. Third, they are the first studies of which we are aware to apply structural modeling techniques to a longitudinal data set in order to evaluate simultaneously the effects of codiagnoses and cognitive/motivational factors on academic and social outcomes of ADHD children. Using this unique approach, three studies are proposed that, as a group, examine: (1) whether ADHD and matched control children differ in their self-perceptions, attributions/control beliefs, and theories of personal attributes, in a domain-specific manner, (2) whether individual difference variables, e.g., goal orientation, self-perceptions, can predict task persistence, post-performance self-evaluations, and post-performance attributions on academic and social tasks in a laboratory setting; (3) whether for both ADHD and normal children, the effects of failure become more pronounced with increasing age; (4) whether patterns of prediction differ for ADHD children with different codiagnoses; and (5) whether information regarding codiagnoses, combined with cognitive/motivational and self-perception variables, can predict academic achievement and social adjustment over time. Examination of these issues may shed important light on our understanding of ADHD.